Increase precision of arithmetic operations to 2^32-1 digits

[JordanRL]

Arithmetic operations are really only limited by the BCMath library in precision, so with the proper redesign a few method signatures, this could easily be increased to the 2^32-1 digits that BCMath supports.

The main reason I shied away from doing this for the initial release is that the trig functions can really only be accurate to the number of decimal places that the constants are available at. However, it is probably more of an edge case to need trig functions to > 100 digits than it is to need arithmetic operations to > 100 digits.

[JordanRL]

This issue was solved by commit 0517b26